Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

Abstract

The electrophotographic photosensitive member includes a surface layer containing (α), (β) and (γ).

What is claimed is: 
     
       1. An electrophotographic photosensitive member, comprising:
 a support; 
 a photosensitive layer formed on the support; 
 wherein a surface layer of the electrophotographic photosensitive member comprises: 
 (α) at least one resin selected from the group consisting of a polycarbonate resin not having a siloxane structure at the end, and a polyester resin not having a siloxane structure at the end; 
 (β) at least one resin selected from the group consisting of a polycarbonate resin having a siloxane structure represented by the following formula (D-S) at the end thereof a polyester resin having a siloxane structure represented by the following formula (D-S) at the end thereof, and an acrylic resin having a siloxane structure represented by the following formula (F-1- 2) at the end thereof: 
 
       
         
           
           
               
               
           
         
         wherein 
         “a” represents the number of the repetition of the structure within the bracket, 
       
       
         
           
           
               
               
           
         
         wherein 
         “d” represents the number of the repetition of the structure within the bracket, and 
         R 55  represents a hydroxyl group or a methyl group; and 
         (γ) at least one compound selected from the group consisting of a methyl benzoate, an ethyl benzoate, a benzyl acetate, ethyl 3-ethoxypropionate, and a diethylene glycol ethyl methyl ether. 
       
     
     
       2. The electrophotographic photosensitive member according to  claim 1 ,
 wherein a content of the above (γ) is not less than 0.001% by mass and not more than 1% by mass based on the total mass of the surface layer. 
 
     
     
       3. The electrophotographic photosensitive member according to  claim 2 ,
 wherein a content of the above (γ) is not less than 0.001% by mass and not more than 0.5% by mass based on the total mass of the surface layer. 
 
     
     
       4. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the polycarbonate resin not having a siloxane structure at the end is a polycarbonate resin A having a repeating structural unit represented by the following formula (A): 
 
       
         
           
           
               
               
           
         
         wherein 
         R 21  to R 24  each independently represent a hydrogen atom, or a methyl group, and 
         X 1  represents a single bond, a cyclohexylidenc group, or a bivalent group having a structure represented by the following formula (C): 
       
       
         
           
           
               
               
           
         
         wherein 
         R 41  and R 42  each independently represent a hydrogen atom, a methyl group, or a phenyl group. 
       
     
     
       5. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the polyester resin not having a siloxane structure at the end is a polyester resin B having a repeating structural unit represented by the following formula (B): 
 
       
         
           
           
               
               
           
         
         wherein 
         R 31  to R 34  each independently represent a hydrogen atom, or a methyl group, 
         X 2  represents a single bond, a cyclohexylidene group, or a bivalent group having a structure represented by the following formula (C), and 
         Y 1  represents a m-phenylene group, a p-phenylene group, or a bivalent group having two p-phenylene groups bonded with an oxygen atom: 
       
       
         
           
           
               
               
           
         
         wherein 
         R 41  and R 42  each independently represent a hydrogen atom, a methyl group, or a phenyl group. 
       
     
     
       6. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the polycarbonate resin having a siloxane structure represented by the formula (D-S) at the end is a polycarbonate resin D having a repeating structural unit represented by the following formula (A′) and an end structure represented by the following formula (D): 
 
       
         
           
           
               
               
           
         
         wherein 
         R 25  to R 28  each independently represent a hydrogen atom, or a methyl group, and 
         X 3  represents a single bond, a cyclohexylidene group, or a bivalent group having a structure represented by the following formula (C′): 
       
       
         
           
           
               
               
           
         
         wherein 
         R 43  R 44  each independently represent a hydrogen atom, a methyl group, or a phenyl group; and 
       
       
         
           
           
               
               
           
         
         wherein 
         “a” and b” each independently represent a number of repetitions of a structure enclosed in the parentheses, 
         an average of “a”in the polycarbonate resin D is not less than 20 and not more than 100, and 
         an average of “b” in the polycarbonate resin D is not less than 1 and not more than 10. 
       
     
     
       7. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the polyester resin having a siloxane structure represented by the formula (D-S) at the end is a polyester resin E having a repeating structural unit represented by the following formula (B′) and an end structure represented by the following formula (D): 
 
       
         
           
           
               
               
           
         
         wherein 
         R 35  to R 38  each independently represent a hydrogen atom, or a methyl group, 
         X 4  represents a single bond, a cyclohexylidene group, or a bivalent group having a structure represented by the following formula (C′), and 
         Y 2  represents a m-phenylene group, a p-phenylene group, or a bivalent group having two p-phenylene groups bonded with an oxygen atom: 
       
       
         
           
           
               
               
           
         
         wherein 
         R 43  and R 44  each independently represent a hydrogen atom, a methyl group, or a phenyl group; and 
       
       
         
           
           
               
               
           
         
         wherein 
         “a” and “b” each independently represent a number of repetitions of a structure enclosed in the parentheses, 
         an average of “a” in the polyester resin E is not less than 20 and not more than 100, and 
         an average of “b” in the polyester resin E is not less than 1 and not more than 10. 
       
     
     
       8. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the acrylic resin having a siloxane structure represented by the formula (F-1- 2) at the end is 
 an acrylic resin F having a repeating structural unit represented by the following formula (F-1) and a repeating structural unit represented by the following formula (F-2), or 
 an acrylic resin F having a repeating structural unit represented by the following formula (F-1) and a repeating structural unit represented by the following formula (F-3): 
 
       
         
           
           
               
               
           
         
         wherein 
         R 51  represents a hydrogen atom, or a methyl group, 
         “c” represents a number of repetitions of a structure enclosed in the parentheses, 
         an average of “c” in the acrylic resin F is not less than 0 and not more than 5, and 
         R 52  to R 54  each independently represent a structure represented by the following formula (F-1-2), a methyl group, a methoxy group, or a phenyl group: 
       
       
         
           
           
               
               
           
         
         wherein 
         “d” represents a number of repetitions of a structure enclosed in the parentheses, 
         an average of “d” in the acrylic resin F is not less than 10 and not more than 50, and 
         R 55  represents a methyl group, or a hydroxyl group; and 
       
       
         
           
           
               
               
           
         
         wherein 
         R 56  represents a hydrogen group, a methyl group, or a phenyl group, and “e” is 0 or 1. 
       
     
     
       9. The electrophotographic photosensitive member according to  claim 1 ,
 wherein a content of the (β) in the surface layer is not less than 1% by mass and not more than 50% by mass based on the total mass of the (α). 
 
     
     
       10. A process cartridge detachably attachable to a main body of an electrophotographic apparatus, wherein the process cartridge integrally supports:
 an electrophotographic photosensitive member according to  claim 1 , and 
 at least one device selected from the group consisting of a charging device, a developing device, a transferring device, and a cleaning device. 
 
     
     
       11. An electrophotographic apparatus comprising:
 an electrophotographic photosensitive member according to  claim 1 ; 
 a charging device; 
 an exposure device; 
 a developing device; and 
 a transferring device. 
 
     
     
       12. The electrophotographic photosensitive member according to  claim 1 ,
 wherein the photosensitive layer comprises a charge generation layer and a charge transport layer formed on the charge generation layer, and 
 wherein the charge transport layer is the surface layer.